It's not known when Numminen, who's consulting with team physicians, will have the procedure and how much time he will miss. The 39-year-old did not report for team physicals Thursday.

"After undergoing examination in connection with his preseason evaluation, the Buffalo Sabres medical team has determined that (Numminen) requires surgery to correct a cardiac condition," general manager Darcy Regier said in a statement.

Numminen, the team's alternate captain this past season, already has had two heart surgeries for an irregular heartbeat, including one in the summer of 2006 after the condition forced him to miss one game and part of another during a playoff series against Philadelphia. Regier said this third surgery will be different from the two previous.

The native of Finland has had a heart murmur since childhood and was diagnosed with a dilated aorta in March 2004 when he was with the Dallas Stars. He missed five games because of the condition before being cleared to play.

Numminen finished with 29 points in 79 games last season.

His agent, Don Baizley, was not immediately available for comment.

"It's early in the process," Regier said. "We'll move along at his schedule and see where he goes with it and what he wants to do."